Nano test tubes fabricated

May 5/12, 2004

Researchers from the University of Florida
have found a way to make minuscule test tubes from carbon and silica nanotubes.
Nanotubes are rolled-up sheets of atoms that can measure less than 1 nanometer
in diameter, and carbon nanotubes occur naturally in soot. A nanometer
is the span of 10 hydrogen atoms.

The nano test tubes could eventually be used -- along with tiny
caps -- to bottle small numbers of molecules such as drugs, DNA, or proteins
and release them in specific places in the human body.

The researchers made the nano test tubes by modifying their template
method of making open-ended nanotubes.

The researchers grow nanotubes in a membrane-like alumina template.
The diameter of the test tubes depends on the diameter of pores in the
template and the length of the test tubes is determined by the thickness
of the template. They were able to make nano tubes that were closed on
only one end by adjusting the template so that the pores were closed on
one end.

The method can be used to make nanotubes from many different materials,
according to the researchers. This opens the possibility of creating tubes
with different biochemical properties. The researchers are also able to
modify the outer surfaces of the test tubes to, for example, encourage
their uptake by particular types of cells.

Nano test tubes could be used practically in 10 to 20 years, according
to the researchers. The work appeared in the March 10, 2004 issue of Nano
Letters.